Safety cap for oil wells



l 1,632,6 1 June 14 1927' F. M. MEcHLlNG 6 SAFETY CAP FOR OIL WELLS Filed Deza. 1. 1924 liavxtentedrJunek 14, `1927.

Y UNITED'-,,STATES5PM-1:N`iOFFICE! Y i 4This invention pertains tosafety caps for [i l-ure 1.; and

rrminrs M. c ivrEcHLrNcr,y or` lwrciri'rii, `iraivsas..yfy i SAFETY car iioriolrriY Applicaten iled` December oil wells'and the like.

'Incertain oil wellloperations such; for instance, asdrilling in a well when the gas orv oil is iiowing, it is customary to provide a cap or .seal for the'upper end ofthe well casingk andV through which the cable works rso as to reduce or cut olif the low of gas oroil'from the well. Such devices A:are ot various types'of lwhichv the ordinary sand Ycap andthe oil saver arewell rknown in the' art. During 'such'operations it" frequently implements suspendedvfrom the cable out ofv becomes necessary to litt the tools or other' the well. It is customary in such cases to place a suitable marken the cable some'distance abovethe implements so that when this markfemerges from the wellA the l operator will be warned that the end of the cable is near. It frequently happens7 however,

" through accident. or carelessness, thatthis mark is disregardedandthe end of the cable arrives at the top of the well without warn-` ing, bringing the tools forcibly `against the sealing cap, so asusually tofdestroy the ycap Vand tearv it from the casing. Occasionally i the cable may be broken by `the impact and the implements dropped to thebottom ot the j lAnother well.y

One 4of the objects of this invention,there?"`y Jr'ore, is to provide a safetycap for the well l casing which may be operated'by the cable tof release the samenfrom the casing" when 'engaged by Va Suitablyarranged part' onthe cable.

I Anotherobjectis to provideav cap kwhich maybe assembled on thek cable while in .the

well.

kengaged with the casing head in that position." 3 i A.1 -41 `of Figure 2y except that the ring 5 and 'the' vhead l" are shown in diametrical section.' y

object is tov provide such a device l which may be set in locking" position and i. 1912471 serial No. `*'isisaaz.y

with a tapered flange 6 adapted for engage- `-ment bythe screws 4to lock the retaining ring lin place on the casinghead and to force the same into lirm engagement with ,the ringQ. The retainingring inay also be provided with a packing ring 7 and an upstanding iiange 8. Thebore of the ring 5 is' provided with one or more inwardly extending `lugs 9' extending circumferentially varound the inn-er bore lof the ring and provided with a sloping lower face 10 for a pur- Y pose which will be'hereinafter more fully described.` Mounted in strueted in two half parts and provided with ylugs 12 adapted to receive bolts 13 for clamp- 'ing the half parts together. The boX k11 may also be provided with a packing ring llt-and a `flange 15 carrying locking screws 16 adapted for engagement with the lower flange v17 of an oil saver4 or other similar casing cap 18. It will be seen lthat by virtue of the various packing `rings 2,7 and 14 and the cap `18the casing is completely "sealed against the escape of gas or oil.

` The box`11is provided with a `series ofl radial channels 19, formed by downwardly extending flanges 190 on thelower end .of

VVthe boX'11, and adapted 'to receive a vseries of dogs 20 for sliding movement therealong. The Vdogs 2O1are thus arranged to slide outwardly to the positions shown in dotted lines in Figure 201 to be retracted to a position Y `the retaining ring andrso as to rest uponthe packing ring' andwithinthe p flange 8 is aboX 11y having a splitfbody con- Y Shownin solid lines in Figli-rc2. Each ldeg `,is providedwith lan 3.opening 21 having beveled"acesjadaptedffor en vagement bythe similarly Vbeveled (faces. or the'V prongs,` 22` oi forkorrspider 23 mounted on-the end ci a vvertical AsleeveQA Whichis mounted for slid- "ing movement Las will presently lie-described.

The sleeve 24 has a split body so that it may be assembled around the cable and bolted together by bolts 25 engaging lugs 26. This sleeve is provided with a central cable channel 27 in alinement with .the cable channel 28 in the box ll. The sleeve '24 has a smooth cylindrical outer surface Q9 having a sliding bearing in aY collar 30 forming part of an extension of the box 11. The extension 40 is also made in two half parts provided with lugs41 for holding the parts together and with bolt holes adapted to receive bolts 42 Jfor bolting they extension 40 on to the main body of the box 11. Thus bolting the extension 4() on to the main body of the box 1 1 completes the channels 19 in which the dogs 20 move.

The sleeve :9A is further provided with a pair Vof lugs `li-."3 in which are mounted apair of guide studs t each adapted to move in a guiding channel 45 formed in the extension 4.0. Each stud 44 is surrounded by a coil spring t6 bearing against the lug #i3 and the end of the extension 40 so as to force the sleeve 24 downwardly in Figure l. It will be seen that as the sleeve 24 is moved downwardly in Figure 1 the prongs 22, cooperating with the beveled faces of the openings 21, will move the dogs 2O outwardly to locking position as shown in dotted lines in Figure 2. rFliese dogs are shown in retracted or unlocking position in F igure 1.

In mounting this device on the casing head, the retaining ring 5 being in position on said head, the box 11 with its assembled parts is set into the retaining ring 5. In this operation the dogs 20, which are maintained in locking position by reason ot the fact that the springs 46 maintain the sleeve 2l in its downward position Figure 1, aie passed through the openings t7 between the lugs 9 ot the retaining ring. lVhen the box has come to a seat on the packing ring 7 `the ends ot' the dogs will be in a position to take under the ends of the lugs 9, and rotation of the box in a clockwise direction will force the dogs against the wedging underface-s 10 of the lugs 9 so as to draw the box firmly down upon the packing ring 7 and secure the same firmly on the casing` head. The normal operation of the well such as drilling or the like is carried on with the device in this position, the cable passing through the cable channel 27 and 28.

Then it becomes necessaryto raise the tools from the well the cable is simply hauled up until the tools reach the top ot the well. Inmany cases a dog or stop is lixed on the cable a short dist-anice above the tools. This' stop, or in its absence the tools themselves, will` then come into engagement with` the 4lower lend of the sleeve 2st. This will raise the sleeve `against the tension of the springs 46. Raising of the sleeve will force the prongs to retract the dogs 20 so that the latter will move out ot engagement with the lugs 9 ot' the retaining ring thereby releasing the box l1 and the cap 18 lrom connection with the casing head. Upon such release. ot course, the box will be carried upwardly with the tools as they emerge from the well.

lt will be seen, therefore, that this invention provides a simple and eli'ective device for protectingl the casing cap against'. accidental damage by being struck by implements rising 'from the well. The device may be assembled on the cable after the same is in the well so that it is not necessary to remove the well tools and thread the cable through the device. A'lter assembly it conveniently and quickly set in place and locked to the casing head. While in place it serves as an effective seal against the cscape of gas or oil and when the tools are lifted from the well it is quickly released from connection with the casing head upon engagement by the tools or other part on the cable.

lVhile the drawing shows thc device in use with an oil saver as a casing cap, it will be understood that any type of casing cap such an oil saver, the ordinary sand cap, or any other type ot casing cap may be used.

It is obvious that various changes may be made in the details of construction without departing from the spirit ot' this invention; it is to be understood, therefore, that this invention is not to be limited to thc spccilic details shown and described.

Having thus described the invention what is claimed is:

l. A device ol the character described, comprising, a split box having a cable channel and adapted l'or assembly around the cable and itor mounting on the casing head, a seat on said box, a casing cap seated thereon, and means tor securing said box on the casing head adapted for automatic release by a part on the cable.

2. A device of the character descril'ied, comprising, a retainer on the casing head, a split box adapted tor mounting on the casing head and tor assembly around the cable. a seat on said box and a cap seated thereon, a dog on said box adapted to engage said retainer, and means adapted for automatic actuation by a part on the cable to release said dog.

A device of the character described. comprising, a retainer ou the casing head, a box adapted for mounting on said retainer and having aA cable channel, packing between said box and said retainer, wedging means for locking said box on said retainer and against said packing, and means adapted for operation by a part on the cable for releasing said locking means.

n s n.

itl() 4. A vdevice of the character described, comprising, a retainer on vthe casing heard, a split box having a cablechannel adapted for mounting onsaid retainer and provided with a seat for receiving a casing cap, packing between said *boX' and said retainer,v wedglng means for locking said box on said retainer and against said packing, and means adapt-ed for operation by a part on the cable for releasing said locking means.

In testimony whereof I aX my signature this 17 th day of November, 1924,

i FIDELIs M. MEGHLING. 

